Explosive.



UNITED STATES. PATENT OFFICE.

JAMES F. OBRIE N, OF CHICAGO, ILLINOIS.

EXPLOSIVE.

romwinz- I .Taall-wi fiom it may concern:

Be itknown that 1, JAMES F. OBRIEN, a

'citizenofthe United States, residing at Chi-' hiumperchlorate and a liquid nitrated coal tar product preferably liquid binitrotolu- *ene; with" carbon, comminuted wood, or

equivalent, and with or without a nitrate of analkali metal, preferably sodium nitrate.

' form.

It may be stated as the broad object of the resent invention to provide an easily manuactured ammonium perchlorate explosive of high efilciency in a water proof, plastic Thereare many other objects and'corre- .sponding'advargages of my present explosive; but all other objectsand advantages of my present explosive may be grouped under the above prime objects. 1

One object is to use materials which may be easily and freely obtained on the market or which may be .manufactur'ed from easily obtainable substances; enabling me to manufacture in largelquaritities from materials obtainable in the United States.

,As to efficiency, it is explained in. the specificat'ion hereinafter how my new explosive hasnot-only a great gas volume without an unduly high temperature but also has a very high speed of action;. so that, although the explosion temperature may be lower than that of dynamite, gelatin or other explo sives which may be compared with my pres ent exp1osive,-t he effective work performed by my present explosive is much greater than the work performed by an equal weight of the best commonly known and used explosives; and in the comparison of my explosive with other explosives on the cost for cost basis, any explosive far exceeds the others in point-of effectiveness for a given expenditure.

The featureof low temperature is one of great moment; and it is caused in no small egreein my explosive by the formation of sodium chlorid during combustion. The

' sodium chlorid absorbs a great quantity of heat, thereby greatly reducing the tempera- 'tll re, audrenders my explosive especially suited for work in coal mines and the like by the comparatively high temperature re- Specification of Letters Patent. Patented Mar. 23 19 15;

Application filed October 14, 1913. Serial no. 795,060.

where an explosive is required to do effective work at low temperature.

The inclusion of binitrotoluene in my composition has mainly two efi'ects;'first, to make the explosive plastic and water-proof and, second, to accelerate the speed of detonation so that the effectiveness of the explosive for blasting of all sorts is greatly increased. Speed is also induced by the carbon.

Ammonium perchlorate has many advantages for explosive use; it is commercially available on the market or by manufacture and it is safe to handle. Its safety is caused quired for its decomposition; but this requirement is also the cause of slow detona tion of the ammonium perchlorate explosives heretofore proposed. Ammonium perchlorate explosives generally show a high temperature and great gas volume, but they are generally lacking in the third prime requisite of explosive efliciencyhigh speed of reaction. In my explosive I increase the speed of action by the use of a liquid nitrated coal tar' product (preferably the so-called the liquid binitrotoluene) and then cause further increase of speed by usin free carbon, in the composition. The b1nitrotoluene in liquid form seems to bring the active ingredients into more intimate contact than can be the case with solid ingredients exclusively; while the ofiice of the free carbon is. to cause initial breaking down of the perchlorate into chlorate. The maximum 7 amount of carbon needed is that sufiicient to cause the reaction; being about 5.5% of the amount of perchlorate; although much smaller amounts give notable -results. The carbon I prefer to supply in the form of finely divided charcoal, or may provide it by partially roasting sawdust so that its surface is more or less carbonized. V r

I prefer to make-my explosive in varyi00- ing grades, varying from a grade of greatest efiective strength to a grade of lowest effective strength; In my explosive of greatest powerI prefer to use only ammonium perchlorate, liquid binitrotoluene, carbon and comminuted wood in the form of saw dust. In my next highest grade I prefer to use a certain amount of a nitrate, preferably so-. dium nitrate; and in the succeeding grades the .amount of sodium nitrate is increased and that of ammonium perchlorate decreased until, in the lowest grade, the maximum amount of sodium nitrate is used. I may use potassium, calcium or barium nitrate or ammonium nitrate; but sodium nitrate is generally to be preferred on account of its cheapness and availability in large quantities on the market.

The following table gives my preferred forms and indicates the range over which the composition may vary.

Liquid bi- NH4C1O4. NaNO;. nitrotolu- Sawdust. C.

one.

Maxi- Calomum Liters Gases ries exploexpanded Gaseous roducts of per sion gas per exp osion.

kilo. temperkilo.

ature.

Litm Degrees per kilo. 6'. H 0 H01 \1 C0 No.0... 877 825 2,240 8,060 slailamint No.1... on 1,149 2,611 6,457 .%;g;,%% No.1-.. 763 782 2,113 6,661 gg g gg' fi No.2... 550 1,103 2,585 5,816 ggg gggg O CO 3 2'053 6'221 rilallamount CO1. No.3... 495 1,048 2,564 5,138 g k gg 0. N011?" 685 715 2,022 5,754 11 0,00, N.

In this table I give the maximum quantities of carbon needed; smaller amounts may be used. The carbon may be in the form of finel divided charcoal; or it may be sup plied by partially carbonizing the sawdust or equivalent material used.

The No. 0 explosive is seen to have the greatest absolute expansion; and it also has the greatest speed of action. It is designed to be primarily useful in open blasting work; its detonation resembles very much that of nitroglycerin. It leaves gaseous products including carbon monoxid and hydro-chloric acid, and for this reason is unsuited to inclosed work, as in mines, etc. Explosive No. 0 is of extremely great strength. Its expanded volume in proportion to its initial weight is greater than that of 75% gelatin dynamite; and its rate oi detonation is so high that its efficient work is greater and better than that of 75% gelatin dynamite.

Explosive No. 1 contains 32% of sodium nitrate; and its formula is-so arranged that there is little or no carbon-monoxid in its resultant gaseous products; the carbon being taken up in carbon dioxid. There is no hydro-chloric acid, the chlorin being depos ited in a sodium chlorid deposit amounting ducing the temperature and absorbing the heat of the explosion. This explosive is of the non-flame type.

Explosives Nos. 2 and 3 are similar to No. 1 excepting that the amounts of ammonium perchlorate are progressively less and the amounts of sodium nitrate are grogressively greater than in No. 1. In each of the explosives Nos. 2 and 3 the composition is made so that the products of combustion are practically the same as in explosive No., 1 except that, in addition, explosives Nos. 2 and 3 also deposit some sodium carbonate. Explosives Nos. 1, 2 and 3 are thus particularly adapted to interior or confined work while explosive No. 0 is particularly adapted to open work.

In order to provide explosives with rates of detonation corresponding to those of Nos. 1, 2 and 3 and with corresponding, or nearly corresponding strength, I have provided explosives 1, 2 3. These explosives 1', 2 and 3 differ from the respective explosives Nos. 1, 2 and 3 only in slight changes of proportions of ingredients; the proportions in explosives 1, 2 and 3 being such that the gaseous products contain carbon monoxid instead of carbon dioxid. The net results of having carbon monoxid in the resultant gaseous products is to greatly in crease the volume of the heated expanded gases. For instance, No. 1' is slightly cheaper to manufacture than No. 1 while its expaned volume is greater than the expanded volume of No. 1.

I provide a series of explosives of graduated strengths suitable both for interior and exterior work. The explosives having carbon dioxid in their gaseous products are to be preferred for general all around work. For work in the open, exclusively, explosives Nos. 1, 2 and 3 and explosive No. 0 are to be preferred on account of greater effectiveness of work performed for a given cost.

With regard to all of the above described explosives I desire to emphasize first the qualities which the liquid bmitrotoluenei imports into the composition. The liquid binitrotoluene not only makes the explosive plastic and water-proof, but adds a great many other desirable physical qualities, chief among which is the adaptability of the powder to cartridge formation. I would also emphasize the ease with which my ex- ,plosive is formed. The liquid binitrotoluene speed of action. With high detonation speed my explosives have great efi'ective strength without a high temperature of combustion. The speed of' action, of course, varies with the different compositions, being greatest in No. 0 and least in Nos. 3 and 3. No. 0 has a speed of action resembling that of nitro-glycerin while Nos. 3 and 3 have a speed of action more like ordinary black powder, having, however, a much greater strength than that of black powder. No. 3 has an effective strength equal to that of about 30% dynamitwNo. 2 to 40% dynamite and No. 1 to 65% dynamite; while the respective rates of detonation are approximately those of dynamites.

With regard to all of the above described explosives it may be particularly stated that they are non-deteriorating under ordinary atmospheric conditions or when exposed to moisture; they will not decompose or change in any manner through long periods of time. None of them can be detonated by mere concussion, friction, jar or vibration; requiring both concussion and heat for detonation, whether confined or unconfined. When supplied with both concussion and heat, as from a cap, they each and all detonate erfectly whether confined or unconfined. hey may each be shot into without detonation. When ignited in the 0 en, without concussion, ex-

black powder, explosive No. 1 burns at a rather lively rate, explosive No. 2 at a slower rate while explosive No. 3 is ignitable but will not continue to burn unless the combustion is forced. These properties make my explosives exceedingly safe to handle and at the same time give positive and reliable results when detonated in the correct manner. My ex losive has all of the desirable features 0 the various nitro-glycerin products without any of their objectionable features; it has their strength'and effectiveness but none of their dangers.

I claim 1. An explosive, comprising ammonium perchlorate not less than twenty parts of weight, sodium nitrate not more than fiftyfive parts by weight, liquid binitrotoluene ten to fifteen parts by weight, saw dust fourteen to twenty-three parts by weight, and free carbon about five per cent. of the weight of the ammonium perchlorate.

2. An explosive, comprising ammoniumperchlorate twenty to sixty-five parts by weight, sodium-nitrate not more than fiftyfive parts by weight, liquid binitrotoluene ten to fifteen parts by weight, sawdust fourteen to twenty-three parts by weight, and free carbon one to three and one-half parts by weight. a

In witness that I claim the foregoing I have hereunto subscribed my name this eighth day of October, 1913.

JAMES F. OBRIEN.

Witnesses:

M, ROBBINS, JAMES T. BARKELEW.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

